Translation and Cross-cultural Adaptation of the SOSG-OQ 2.0 Questionnaire into Brazilian Portuguese

Objective:  To perform the cross-cultural adaptation and translation into Brazilian Portuguese of the Spine Oncology Study Group – Outcomes Questionnaire 2.0 (SOSG-OQ 2.0) to enable its application to Brazilian patients and to allow Brazilian researchers to use a questionnaire that is on trend in the scientific literature. Materials and Methods:  The present is a basic, non-randomized, non-comparative study. The translation followed the proposal by Reichenheime and Moraes, mainly for the semantic equivalence and measurement equivalence sessions, as well as the recommendations by Coster and Mancini mainly in the translation stage. The stages were as follows: first – translation into Brazilian Portuguese; second – back-translation; third – semantic comparison; fourth – validation of the final construct. Results:  The translations of the SOSG-OQ 2.0 made by three translators presented a high degree of similarity for most questions. The translators kept all question titles and subtitles, as well as their internal and external orders. Two sworn translators, with native proficiency in English, performed the back-translation of the amalgamated text. Both back-translations were quite similar, and any differences were solved through consensus between the main author and the sworn translators, and the translated text was considered the final version. Conclusion:  The present study shows a translated version of the SOSG-OQ 2.0 with semantic validity with the original version published in English. As such, researchers can apply the questionnaire to the Brazilian population, adding another tool for spine surgeons to improve the monitoring of this complex group of patients.


Introduction
In Brazil, since 2000, cancer has been the second leading cause of death after heart disease. 1 The prevalence of metastatic spinal tumors is higher than that of primary tumors at this location. 2,3Metastatic spinal disease increases the morbidity related to the primary condition, directly impacting the patient's quality of life. 2,4,5t is not uncommon for patients with metastatic disease to present with dysfunctions in several body systems, and they may undergo different treatments, including chemotherapy and/or radiotherapy. 6][8] Multiple tools are currently available to study the clinical outcomes of patients with metastatic spinal tumors.However, they are nonspecific and usually analyze a single variable. 9For instance, the Frankel scale and the American Spinal Injury Association (ASIA) impairment scale quantify (classify) the degree of neurological injury. 10,11In addition, quality-oflife questionnaires filled out by patients determine how they perceive their quality of life/health status, enabling them to identify the impact of a procedure or condition on the subject quality of life/health status. 12,13In spinal surgery, the most applied quality-of-life questionnaires are the Oswestry Disability Index 14 and the Neck Disability Index, 15 which specifically quantify the impact of a condition on the selfperceived quality of life regarding the lumbar spine and cervical spine respectively.Moreover, broader questionnaires, such as the EuroQoL Five Dimensions (EQ-5D) or the 36-Item Short Form Survey (SF-36), quantify quality of life more comprehensively, without focusing on a specific condition or location, enabling the comparison of patients with different diseases or treatments using the same score. 16,17Lastly, quality-of-life impact scores filled out by physicians, surgeons, or both, such as the Eastern Cooperative Oncology Group (ECOG) score, classify how much the tumor impacts the patient's activities.On the ECOG, 0 equals regular quality of life, while 5 indicates death. 18espite being validated and helpful in the follow-up and evaluation of patients with metastatic tumors, none of these questionnaires focus specifically on patients with spinal tumors.As such, the literature diverges on the best combination of questionnaires to follow-up patients with metastatic spinal tumors.For instance, Street et al. 9 recommend ECOG and SF-36, while Choi et al. 19 prefer the EQ-5D.

Conclusion:
The present study shows a translated version of the SOSG-OQ 2.0 with semantic validity with the original version published in English.As such, researchers can apply the questionnaire to the Brazilian population, adding another tool for spine surgeons to improve the monitoring of this complex group of patients.

Palavras-chave
► coluna vertebral/ cirurgia ► pesquisas e questionários ► metástase neoplásica ► qualidade de vida ► traduções The lack of questionnaires for the specific evaluation of a given condition led the Spine Oncologic Study Group (SOSG) to develop an outcomes questionnaire (SOSG -Outcomes Questionnaire, SOG-OQ) to assess the quality of life of patients with metastatic spinal tumors. 20Furthermore, a study 21 showed that the SOSG-OQ was superior to the 3-Level Version of the EQ-5D (EQ-5D-3L) in patients with metastasis, lymphoma, or myeloma.Moreover, the SOSG-OQ was more effective than the Patient-Reported Outcomes Measurement Information System (PROMIS) 22 in analyzing the quality of life of patients with spinal metastasis; however, the PROMIS was more effective in assessing physical function and pain, according to a study by Paulino Pereira et al. 23 Although specifically designed for patients with spinal metastases, the SOSG-OQ still contained certain internal inconsistencies, and items in selected subdomains did not correlate as effectively. 21,24hus, in 2018, Veersteg et al. 24 performed a psychometric study on the SOSG-OQ, and developed an updated version.To solve discrepancies in the first version of the SOSG-OQ , the authors divided the original question 8 (on bowel and bladder function) into 2 separate questions to facilitate the answer, since often only the bowel or bladder is dysfunctional.Furthermore, they moved questions 7 (on walking assistance) and 20 (on leaving the house) to the physical function domain; question 16 was moved to the pain domain, and question 15 (on energy level) was removed, as it was not associated with any domain and did not provide enough significant information. 24Then, the SOSG-OQ 2.0 construct was compared with the Numeric Rating Scale (NRS) for pain and the SF-36 in patients with spinal metastasis, and a strong correlation was found between the questionnaires. 24s such, the present study aimed to perform the crosscultural adaptation and translation of the SOSG-OQ 2.0 into Brazilian Portuguese, to enable its application to Brazilian patients.

Materials and Methods
The present is a basic, non-randomized, non-comparative study.

Translation and cross-cultural adaptation process
The translation and cross-cultural adaptation of an instrument involve multiple steps to ensure that the translated construct is valid and equivalent, and that it also makes sense for the target audience. 25The process begins with multiple translations of the original questionnaire; then, a synthesis of these texts forms the amalgamated translation.After a consensus on the translation, a group of translators (with native proficiency in the original language) performs back-translations (BTs) of the document, which are then synthesized to obtain the final BT.An expert committee compares the BT with the original version to check for any discrepancies between the previous texts.If there are few or no discrepancies, the construct undergoes psychometric and validity assessments in the target population. 25,26he translation followed the proposal by Reichenheime and Moraes, 26 mainly for the semantic equivalence and measurement equivalence sessions, and the recommendations by Coster and Mancini, 27 mainly in the translation stage (►Fig. 1).
Step 1: individual translation into Brazilian Portuguese of the SOSG-OQ 2.0 by 3 Brazilian researchers.Through a comparison of the three translations a consensual, unified version was developed, called amalgamated translation.During the translation stage, the reviewers were asked to make any required changes to elements of the questions that were not so familiar to the Brazilian population.
Step 2: Two proofreaders, certified language studies specialists with proficiency in English, analyzed the amalgamated translation.The generated texts were called amalgamated BT.
Steps 3 and 4: Another translator (called final translator), who had not been involved in any of the translations and BTs, compared the amalgamated BT with the original version to provide an opinion on the similarity of the questionnaires, both in denotative and connotative aspects.This translator evaluated the questions as unchanged, slightly changed, and extremely changed.

SOSG-OQ 2.0
The SOSG-OQ 2.0 was developed in 2018 as an adaptation of the original SOSG-OQ to improve the internal validity of its domains and its correlation with other previously-validated constructs. 24The reliability values of the questionnaire in the test-retest evaluations ranged from 0.58 to 0.92 between domains.In addition, the SOSG-OQ 2.0 presented an excellent correlation with the SF-36.The construct consists of 27 (20 preoperative and 7 postoperative) questions.The preoperative questions constitute five domains: physical function (6 questions); neurological function (4 questions); pain (5 questions); mental function (2 questions); and social function (3 questions).All questions contain 5 items with scores ranging from 1 to 5. To obtain the total score on the SOSG-OQ, one needs to reverse the score on the items, that is, 1 ¼ 5, 2 ¼ 4, and so on.The higher the score, the worse the quality of life.The score of the seven postoperative questions is a percentage of the maximum potential points (rule of three). 21

Results
The translations of the SOSG-OQ 2.0 by the 3 translators presented a high degree of similarity for most questions.The translators kept all question titles and subtitles and their internal and external orders.
As for the translation of the questions per se, there was little discrepancy between the reviewers, with only two questions showing significant divergence between them (►Table 1).There were some disagreements in the translation of the alternatives (►Table 2).With these divergences resolved, we prepared the amalgamated translation.

Back-translation and Final Version
Two sworn translators, with native proficiency in English, performed the BT of the amalgamated text.Both BTs were quite similar, and any differences were solved by consensus among the main author and the sworn translators (►Table 3).
Since none of the questions or alternatives was "extremely changed" compared with the original questionnaire, the amalgamated translation was the final considered version of the questionnaire (►Table 4).

Discussion
Metastatic spinal tumors can cause different clinical manifestations and considerably impact the quality of life of the Você precisa de ajuda de outras pessoas para sair de casa?
Você precisa de ajuda de outras pessoas para sair de casa?
When I feel pain, it is awful, and I feel that it overwhelms me.
Quando eu sinto dor, é uma dor horrível e insuportável.patients.This impact is not restricted to the affected spinal segment, due to the systemic characteristic of the disease. 4,28,29In addition, the existing questionnaires to assess the clinical outcomes of patients with metastatic spinal tumors were nonspecific and did not involve all variables. 9,20Thus, the SOSG-OQ 2.0 was developed in an attempt to quantify the impact of the condition on quality of life. 24owever, to date, no version of the questionnaire in Brazilian Portuguese had been published.
In the present study, we performed the translation into Brazilian Portuguese and cross-cultural adaptation of the SOSG-OQ 2.0.Despite some discrepancies among the initial translations, mainly regarding adverbs of degree (very, enough, little etc.) reaching consensus among translators was simple.Likewise, the cross-cultural adaptation required few changes (such as altering use of chopsticks to use of cutlery), since it was originally developed by American and European researchers, whose habits tend to be very similar to those of Brazilians.Similarly, in a study by the Brazilian Spine Study Group and Brazilian surgeons the Frailty Index 30 was translated; despite discrepancies regarding some items, few cross-cultural adaptations were required. 31he SOSG-OQ consists of 27 questions, including 20 on the symptoms and impact of the disease on the patient's quality of life, plus 7 questions on how the patient feels about the surgical procedure. 20,21In psychometric and consistency evaluation studies, 21,24 the SOSG-OQ correlated strongly with the quality-of-life scores on the EQ-5D and SF-36.In addition, its subgroups presented strong internal consistency. 21,24he potential improvement in the follow-up and evaluation of the impact of spinal neoplasms using the SOSG-OQ has led several authors to translate it into their native languages.Luksanapruksa et al. 32 performed the translation and cross-cultural adaptation into Thai, and they reported that the domains pf the translated version maintained a high internal consistency (Cronbach alpha > 0.7) and that the questionnaire presented a strong correlation with the 5-Level EQ-5D (EQ-5D-5L).Likewise, Brodano et al. 33 reported the validity of the Italian version in terms of the internal domains and their correlation with the SF-36 subdomains, as well as a high consistency among questionnaire items.
Yin et al. 34 showed that the simplified Chinese version presented a strong correlation with the EQ-5D-5L and SF-36, an excellent internal consistency among its subgroups, and good intra-observer results.A group of researchers 35 recently demonstrated that the physical function, pain interference, and depression domains of the PROMIS presented a strong correlation with the SOSG-OQ.
Regarding the impact of the SOSG-OQ on decision-making, a 2020 study 36 on the benefits of potentially predicting scores on health-related quality of life (HRQoL) instruments after the surgical treatment of spinal neoplasms pointed out that the 2 questionnaires most beneficial in terms of the prediction of postoperative outcomes were the EQ-5D and the SOSG-OQ. 36Furthermore, an article published in 2021 37 proposed the development of a summarized version of the SOSG-OQ especially focused on utility units, which would enable its use in the analysis of decisions, such as the one to convert these utility units into quality-adjusted life years (QALYs).
The present study has limitations, mainly the non-validation of the Brazilian Portuguese version due to the difficulties in obtaining sufficient data.However, it will serve as a basis for future validation.We believe that validation studies of our version of the SOSG-OQ are required for the internal consistency of its constructs and to determine its correlation with already established questionnaires, such as the EQ-5D.

Fig. 1
Fig. 1 Flowchart of the translation of the SOSG-OQ until the final version.

Table 1
Discrepancies in the translation of questions

Table 3
Examples of discrepancies and consensus between the two back-translations

Table 2
Examples of discrepancies regarding the translations of answer items Rev Bras Ortop Vol.59 No. 1/2024 © 2024.The Author(s).